The goal of this proposal is to develop a STAT palm-sized blood counter for monitoring complete blood counts (CBC) during emergencies. Changes in blood counts can reflect acutely worsening medical conditions. For instance, a rapidly rising white blood cell count may occur during infections or leukemic blast crises. Hematocrit values may rapidly decline in traumas, gastrointestinal bleeds, and post-procedure recoveries. Platelet values may drop significantly during chemotherapy and idiopathic thrombocytopenic purpura. During these situations, close and frequent monitoring of a patient's CBC is a must to deliver the best care and treatment, whether it be blood transfusions, platelet transfusions, or drug administrations. The proposed blood counter samples a fingerstick of blood from the patient and analyzes it in real-time at the patient's side for point-of-emergency clinical decision making. This is in contrast to today's CBC measurement technologies, which require a benchtop instrument and a trained technician. The central hypothesis for this Phase I-III SBIR effort is this: microfluidic technology can be utilized to develop an integrated palm-sized blood counter that requires only a pinprick of blood. The proposed 12-month $100,000 Phase I research is based on work at the DNA Medicine Institute that includes developments in flow-focusing, detection, micromixing, and integration. For each of these areas, we have conceived or discovered novel approaches that can potentially augment accuracy, increase integration, and diminish the size of our blood counter. These miniaturized advances will be explored in our Specific Aims. Specific Aim 1 will identify the optimal flow-focusing and detection format for measurement of cell counts and volume. Specific Aim 2 will characterize prototype low Reynolds number micromixers with respect to mixing efficiency, functional Re, and blood compatibility. Specific Aim 3 will assess the performance of our prototype integrated microfluidic blood counter in measuring hematocrits relative to a predicate method. Successful completion of Phase I will support our core hypothesis and lead to a Phase II effort that will be utilized for developing a palm-sized prototype that is capable of bringing full hematology capabilities, a complete CBC and 5-part differential, to point-of-emergency situations. Phase III will comprise of development, FDA approvals, and commercialization. The resulting product would be applicable for emergencies in a wide-range of settings including ambulances, inpatient rooms, operating rooms, medical offices, and resource-starved settings. PUBLIC HEALTH RELEVANCE: NARRATIVE This research is relevant to public health because rapid diagnosis of blood counts can be the difference between life and death. The palm-sized blood counter product is designed to provide much needed medical information during critical emergencies.